In my aforesaid application, Ser. No. 796,178, there is disclosed and claimed, a portable air compressor attachment adapted to be driven by the chuck of a portable power drill. The air compressor attachment includes a housing having a longitudinal axis; and a casing is disposed within the housing and has a longitudinal axis substantially aligned with the axis of the housing, such that the casing and housing have an annular space therebetween. The casing includes a cylinder, and a piston is guided for reciprocation in the cylinder along the longitudinal axis of the housing. A first shaft is journaled in the housing, substantially aligned with the longitudinal axis thereof, and the first shaft is driven by the chuck of the portable power drill. A second shaft is mounted in the housing, substantially at right angles to the first shaft, and first and second bevel gears are carried by the first and second shafts, respectively, to provide a speed increase therebetween. A suitable motion-converting means, such as a crank mechanism, is disposed between the second shaft and the piston; and air inlet and exhaust means are associated with the cylinder. The housing includes a forward portion, and a compressed air discharge means in the forward portion of the housing communicates with the air exhaust means and, preferably, is substantially aligned with the longitudinal axis of the housing. Accordingly, the portable power drill may be held in one hand of the user, while the air compressor attachment may be held in the other hand of the user, without regard to the heat generated by the reciprocation of the piston in the cylinder.
With this structure, the air compressor attachment (or accessory) is small, compact and lightweight and may be dropped into the tool box of a professional mechanic or a do-it-yourself ("D.I.Y.") home craftsman. The air compressor is readily driven by any motive power source, such as a power drill and, more particularly, a portable electric drill. Studies have shown that, in the United States, three out of four households have a power drill, and that nine out of ten "D.I.Y." households have a power drill. With this widespread availability of power drills, there are many uses in and around the home, garage, basement workshop, or lawn and garden for an air compressor driven by a power drill.